I am using GMT6.5 (windows). I have calculated coulomb stress change on nodel planes. But I don’t know how to plot the output in GMT.
The output file looks like this:
|year|month|day|hour|minute|lon.|lat.|depth|magnitude|strike1|dip1|rake1|shear1|normal1|coulomb1|strike2|dip2|rake2|shear2|normal2|coulomb2|
|2022|9|17|13|41|121.160797|23.084|8.61|6.6|201.449997|61.540001|15.04|1.461529|-0.453529|1.280118|104.150002|76.809998|150.699997|1.46163|0.68777|1.736738|
As far as I can tell, your output is a single point (point source approximation?). There’s nothing to be plotted here other than a single point with two Coloumb estimates each per nodal plane.
The coulomb stress change is calculated on nodal planes. For the learning purpose I only shown one point. However the output looks like this:
| year | month | day | hour | minute | lon. | lat. | depth | magnitude | strike1 | dip1 | rake1 | shear1 | normal1 | coulomb1 | strike2 | dip2 | rake2 | shear2 | normal2 | coulomb2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| - | - | - | - | - | (deg) | (deg) | (km) | - | (deg) | (deg) | (deg) | (bar) | (bar) | (bar) | (deg) | (deg) | (deg) | (bar) | (bar) | (bar) |
| 2022 | 9 | 17 | 13 | 41 | 121.160797 | 23.084 | 8.61 | 6.6 | 201.449997 | 61.540001 | 15.04 | 1.461529 | -0.453529 | 1.280118 | 104.150002 | 76.809998 | 150.699997 | 1.46163 | 0.68777 | 1.736738 |
| 2022 | 9 | 17 | 14 | 35 | 121.178001 | 23.0993 | 9.33 | 5.33 | 233.419998 | 35.939999 | 88.510002 | 0.306129 | -0.698723 | 0.02664 | 55.25 | 54.080002 | 91.080002 | 0.306196 | -1.106357 | -0.136347 |
| 2022 | 9 | 17 | 14 | 45 | 121.193703 | 23.116699 | 5.84 | 5.84 | 194.039993 | 63.25 | 23.610001 | 0.091454 | -2.364743 | -0.854443 | 92.910004 | 69.040001 | 151.190002 | 0.091477 | -0.843406 | -0.245885 |
| 2022 | 9 | 17 | 16 | 44 | 121.182999 | 23.1012 | 8.8 | 4.57 | 80.989998 | 41.509998 | 83.900002 | -0.368312 | -0.448963 | -0.547898 | 269.109985 | 48.779999 | 95.370003 | -0.368292 | -0.120805 | -0.416615 |
| 2022 | 9 | 17 | 18 | 3 | 121.311798 | 23.0993 | 15.51 | 4.92 | 219.240005 | 37.450001 | 109.730003 | -0.653374 | 1.499737 | -0.053479 | 14.93 | 55.080002 | 75.5 | -0.653351 | 0.122689 | -0.604275 |
| 2022 | 9 | 17 | 19 | 2 | 121.207497 | 23.0165 | 9.86 | 3.87 | 10.5 | 27.35 | 118.940002 | -0.997402 | 0.061166 | -0.972935 | 158.589996 | 66.290001 | 75.949997 | -0.997526 | -0.015321 | -1.003655 |
| 2022 | 9 | 17 | 20 | 28 | 121.314796 | 23.102301 | 13.55 | 3.74 | 347.809998 | 51.459999 | 29.67 | 0.641695 | 0.427562 | 0.81272 | 238.270004 | 67.220001 | 137.479996 | 0.641436 | 3.355614 | 1.983681 |
| 2022 | 9 | 17 | 21 | 11 | 121.339699 | 23.1003 | 17.24 | 4.03 | 227.300003 | 37.380001 | 112.449997 | -0.922702 | 1.904062 | -0.161077 | 19.83 | 55.869999 | 73.730003 | -0.922841 | 0.16517 | -0.856773 |
| 2022 | 9 | 17 | 21 | 41 | 121.330704 | 23.1103 | 15.88 | 4.25 | 217.860001 | 33.880001 | 110.169998 | -0.893805 | 1.543683 | -0.276332 | 13.99 | 58.439999 | 76.959999 | -0.893618 | 0.28914 | -0.777962 |
There are more rows…
You’ll plot Coulomb stress from one nodal plane at a time, using a grid of lat, lon, Coulomb stress. This is already documented in section 5.9 of the Coulomb manual: https://pubs.usgs.gov/of/2011/1060/of2011-1060.pdf
When you have the xyz grid, you can follow this GMT example to make your figure: https://docs.generic-mapping-tools.org/6.2/gallery/ex02.html
The only step missing here is converting your xyz to grid before using grd2cpt, which you will do by using the xyz2grd GMT function.
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